Cabinet knob



FIG. 1 is a front perspective view of a cabinet knob showing my new design;

FIG. 2 is a longitudinal side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a lateral side elevational view thereof; and,

FIG. 5 is a bottom plan view thereof.

The broken lines form no part of the claimed design. 

The ornamental design for a cabinet knob, as shown and described. 